A TFT array is a key component of the liquid crystal display (LCD). FIG. 1 is a schematic structural view of a conventional TFT array 100. The TFT array 100 includes a plurality of pixel units 102, a plurality of scan lines 104 and a plurality of data lines 106.
The pixel units 102 are electrically connected to the scan lines 104 and the data lines 106. Each of the pixel units 102 has a transistor 108, a liquid-crystal capacitor (CLC) 110 and a storage capacitor (CS) 112 wherein the transistor 108 has a gate electrode G, a source electrode S and a drain electrode D. The gate electrode G is connected to the scan line 104, the source electrode S is connected to the data line 106, and the drain electrode D is commonly connected to the CLC 110 and the CS 112 (as shown in FIG. 1) or commonly connected to the common line (not shown).
When a positive voltage is applied to the first scan line (SL1), the thin transistor 108 connected to the first scan line (SL1) turns on so that the pixel electrodes of the CLC 110 are electrically connected to the data lines 106 and the video signal is transmitted to the pixel electrode of pixel unit via the data lines 106 correspondingly for charging the CLC 110 to be a proper voltage level. In other words, the CLC 110 of the pixel unit 102 is charged to drive the liquid crystal molecules within the liquid crystal layer for displaying the image on the LCD panel. Meanwhile, the CSs 112 connected to the data lines 106 are charged wherein the charged CSs 112 are used to maintain the voltage potential of the CLC 110 to be a predetermined value for keeping the voltage potential to be constant in the both terminals of the CLC 110 by the charged CSs 112 before the data lines are updated. Afterwards, a negative voltage is applied to the thin transistor 108 to turn off the thin transistor 108 until the video signal is written to the vertical data lines 106 next time wherein the charges is stored in the CLC 110. The next scan line (SL2) 104 is activated and the video signal is transmitted to the pixel electrodes of the pixel unit P2 102 via the data lines 106 correspondingly.
However, it is required to turn off the thin transistor 108 connected to the scan line (SL1) before the CLC 110 and the CS 112 of the pixel unit P2 102 on the scan line (SL2) are charged, which results in a lot of charging duration. Consequently, there is a need to develop a novel TFT array structure to solve the aforementioned problem of the long charging duration.